- Explanation of the term "semiconductor"
- Fabrication of semiconductor devices
- Challenges in the production of semiconductor devices
- Manufacturers of semiconductor devices
Electricity can only flow in one direction through a semiconductor
. Semiconductors are used to manufacture transistors and diodes. A transistor is the central component of a computer. The conductibility of a transistor can be changed using a control circuit. Thereby, the conductor can have a "conductive" or "non-conductive" state.
- Manufacturing must be done in pristine conditions
- Very complex process
Personalized This is the basic principle of the entire field of digital technology. Semiconductors
can be made out of monocrystalline, polycrystalline or an amorphous form. Monocrystalline semiconductors are used primarily for the computer industry. Polycrystalline and amorphous semiconductors are found, among other areas, in solar technology. Monocrystalline semiconductors
are produced using a specially cultured silicone crystals. These cylinders, that are about a metre long, are called "ingots"and regular crystal lattice. This single crystal cylinder is cut into slices. The slices are then coated using a photo-chemical finish, exposed to light and the etched. Thereby, they will be able to obtain complex, microscopic structures. With further processing steps, these structures become transistors. These slices are called "wafers".
The produced transistors
are then grouped into regular units and are separated from the wafer. The computer chips with connectors are then made out of the wafer pieces by pouring it into resin. This can then be built onto a main board. The process for polycrystalline and amorphous semiconductors devices is similar. Semiconductor devices
are fabricated in very pristine conductions. Even the production of monocrystalline semiconductors is sensitive to interference. Until the chip is poured into the resin, every operational step needs to be conducted in very pristine conditions. The smallest amount of dirt, even a single dust particle on the microchip, could immediately damage the product. The whole process of semiconductor device fabrication is, in its complexity, incomparable to any other industrial sector. Only specialists and highly-skilled workers should be involved during the manufacturing of semiconductor devices. Machines used for the fabrication of semiconductor
ingots are put into special melting ovens. They are cut into slices with mechanical machines such as metal band saws
. The microscopic structures on the slices are brought about using immersion lithography equipment. The microchips
themselves are then fabricated using special machines.
The manufacturing of these microchips requires a larger variety of machines and equipment. This is particularly the case for the clean-room technology and quality control of the microchips. Because of the high risk of damage during the manufacturing process, the safety measures taken by the manufacturer is of great importance. Strong air filter systems and elaborate control systems should keep the scrap rate to a minimum.
There are only several large companies that produce computer chips. The most well known are INTEL and SAMSUNG. The production requirements of computer chips change constantly through developments in productivity. This means that there are numerous suppliers of a large variety of special systems. Well-known manufacturers of machines, that are used for the fabrication of semiconductor devices, are NIKON, CARL ZEISS